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royal duke

British  

noun

  1. a duke who is also a royal prince, being a member of the royal family

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Example Sentences

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The Prince of Wales, Princess Royal, Duke of Edinburgh and Vice Admiral Sir Tim Laurence were also in attendance at what is considered one of the highlights of the royal calendar.

From BBC

However, it is thought Prince William will be the only Royal Duke to pay homage to King Charles.

From BBC

Eric Pierre, a pastor who teaches fifth-grade English in the Bronx, has taken up an additional title this summer: royal duke.

From New York Times

From one royal duke and duchess, a traditional shot: relaxed grins, rumpled jeans, and armfuls of beaming children.

From The Guardian

Traditionally, just before a marriage, the monarch puts out what are called "letters patent," a kind of royal wedding gift to the son or grandson, making him a royal duke.

From Los Angeles Times